This invention relates in general to elastomeric compositions, and in particular to compounds made with a liquid nitrile rubber.
Liquid nitrile rubbers are conventionally used in a minor amount as a plasticizer or processing aid in combination with a solid elastomer in preparing a rubber compound. It has not previously been thought to use liquid nitrile rubbers as the base elastomer for making a compound, and then to cure the liquid nitrile rubbers.
Rubber compounds are conventionally made by mixing the elastomer(s) and other chemicals together in an organic solvent, or in an aqueous solvent to prepare an emulsion. It has not previously been thought to prepare a liquid nitrile rubber compound without the use of a solvent, and there has been no suggestion how to prepare the compound in a solventless process. Such a process is contrary to the conventional thinking.
In one embodiment, this invention relates to a solventless liquid nitrile compound. The compound includes a liquid nitrile rubber. The compound also includes a curing agent selected from sulfur and/or sulfur donors. The curing agent is present in an amount of at least about 3% by weight of the compound. The compound contains substantially no solvent.
In another embodiment, this invention relates to a solventless liquid nitrite compound. The compound includes a liquid nitrite rubber. The compound also includes a nonsulfur curing agent. The curing agent is present in an amount of at least about 5% by weight of the compound. The compound contains substantially no solvent.
Various objects and advantages of this invention will become apparent to those skilled in the art from the following detailed description of the preferred embodiment.